There is a wide variety of materials employed in personal care and cosmetic preparations that is subject to microbial attack and concomitant deterioration. For example, oils such as cocoanut oil, sesame oil, peanut oil and the like, are frequently used in cosmetic and personal care preparations as vehicles, carriers and emollients. Mold spores and similar organisms are known to be able to thrive on such oils. The net effect is ultimate deterioration of preparations containing such oil vehicles. The result is not only an economic loss but often the user is unsuspectingly and unnecessarily exposed to potentially harmful organisms.
Other materials are also susceptible to microbial attack. For example, organic nitrogen compounds such as nitrogeneous surfactants, proteins, protein hydrolysates, and the like used in popular cosmetics and shampoos are utilized by a wide variety of microorganisms thereby shortening the shelf-life of preparations incorporating these materials.
Thus, there is a need for protecting or preserving preparations subject to microbial attack against the growth of these harmful microorganisms so as to extend the shelf-life and improve the quality of the preparations.
It should be noted that even if cosmetics and personal care preparations are formulated under the most carefully controlled conditions designed to minimize microbial contamination, ultimately the container is opened by the user and thereby brought into contact with air borne organisms or organisms carried by the user. Thus, control of manufacturing conditions is not sufficient in itself to assure desirable resistance of the preparation to microbial deterioration.
Preservation of cosmetics and personal care products by use of additives is not a simple task. Many materials, for example, are known germicides or bactericides. Unfortunately, few highly effective antimicrobials are sufficiently safe for use in contact with humans. Additionally, any preservative employed must be easily combinable with typical cosmetic and personal care preparations without detrimentally affecting the overall physical properties of such preparations.